Search This Blog

Sunday, May 13, 2012

Recycling Laptop batteries

What to do with those old Li-ion cells out of a old laptop battery??

Maybe a flash light!

Schedule 80 3/4 PVC is the perfect size for these cells.


It's pretty simple construction, I used a hole saw to cut a proto board in to a nice circle and soldered on some super bright LED's.

Put a loop of wire on the bottom for the positive contact,

which you really can't see that well in these pics. Drilled through the cap and put a spring in it to make the negative connection. 

It's just help together with the interference fit on the PVC. It's my favourite so far, probably because of the size.


I did a little more on the actual mounting of the LED's and the connection to the batteries.

Drilled holes in a washer and bolted the whole thing together.

Just Regular white LED's I did not have any super bright ones.

So I left this one on for 3 days!!! Still was working even though it was quite a bit dimmer, but let's not forget these are USED batteries that no longer worked in the laptop. Plus these are low power LED's so I know I won't see the same performance out of the other prototypes.

A notch in the top for the bolt in the head.


The Illuminator
900 LM LED's This thing is BRIGHT!

This one has a switch in it.
A grove for the negative wire

 The Spring set up

One Bright Mofo

I need to work out a better switch, but this is what I had on hand. 

more to come



  1. how do you recharge this lamp?

  2. You need a metal heatsink behind those high-output LEDs or you'll cook them to death. You also need a protection circuit for the 18650 cells, or you'll overdischarge them - they should never get below 2.7V under discharge or 3V open-circuit.
    There's also no way in hell that thing is putting out nine hundred lumens.

    1. And why not? The Torch uses 4100 lumens. That's the best flashlight in the world. The cheap as dirt flashlights can pull off 900 lumens no problem.

  3. This is a nice and interesting project. Good luck with it. At work there is a big bucket of these batteries. This does not make it easier to resist the temptation to take few home. :)

    Fallingwater. He does not say it's 900 lumens. He is using 900 LM LED's which may, or may not, give out that amount in this project. Heat sink is not really needed if they are not working at full power.
    Rodrigo. Almost any RC charger can charge these cells.

  4. This is commendable work. Batteries can be detached without opening the whole system, making it one of the easiest parts to use again, either as a part of a new refurbished laptop or as a part of something else, just like what you have shown in this blog. Moreover, batteries contain heavy metals which are harmful to our soil. Recycling it would lessen the threat of toxins in our environment.

    Benita Bolland

  5. casas prefabricadas www casasde info es una empresa donde podrás encontrar los últimos planos y diseño de casas prefabricadas o de construcción tradicional Un catálogo de más de 1000 modelos exclusivos para la construcción de casas prefabricadasClick here to visit this site